A material bed roller mill of the aforesaid type is known for example from DE-OS 35 35 406. In this case two opposing slide-like covers are provided at a certain height above the roller gap and at the lower end of a filling shaft. These covers are capable of being moved towards one another in a straight line in their chosen inclination in order thereby to be able to regulate the material feed width and/or the height of the material column bearing on the rollers.
The object of the invention is to improve the known material bed roller mill in such a way that with a relatively simple construction the pressure exerted by the column of material to be ground above the rollers can be utilised to the greatest possible extent for material bed crushing even with a fluctuating material feed.